- So, they've just figured this out? Of course, the disease
spreads through contaminated environment. Now, let's hope they can put
1 and 1 together and get TWO. Ergo, if CWD gets into the environment
via infected animals, do we continue to have mass slaughters? NO.
- I am amazed at how long it took for the "EXPERTS"
to figure out that CWD prion disease aka mad cow disease of deer, elk and
moose, spreads via environment as well as, animal-to-animal contact: both
horozontal and vertical transmission.
- Patricia Doyle
- CHRONIC WASTING DISEASE UPDATE 2004 (02)
- A ProMED-mail post ProMED-mail a program of the International
Society for Infectious Diseases
- Source: National Science Foundation, 12 May 2004 [edited]
- New Research Supports Theory That Indirect
Transmission Of CWD Is PossibleIn Mule Deer
- National Science Foundation May 12, 2004
- A team of researchers has reported that chronic wasting
disease (CWD) can be transmitted through environments contaminated by whole
carcasses or excrement of animals infected with the pathogen that causes
CWD. The research confirms long-held theories that CWD can be indirectly
spread through environmental sources, in addition to direct interactions
between infected and healthy mule deer.
- Funded by the National Science Foundation (NSF) and the
National Institutes of Health, the study results were published online
last week in the journal Emerging Infectious Diseases
- The authors are Colorado Division of Wildlife (DOW) veterinarians
Michael Miller and Lisa Wolfe, Colorado State University (CSU) scientist
Thomas Hobbs and University of Wyoming scientist Elizabeth Williams.
- "Diseases like CWD are poorly understood and of
rising concern," said Sam Scheiner, program director in NSF's division
of environmental biology, which funded the research. "This study provides
significant new information showing the potential for transfer of the infection
through the environment after many months. The knowledge will substantially
alter how we manage the disease in wild and domestic animals."
- Based on anecdotal observations, "we have long suspected
that CWD could be transmitted when healthy deer were exposed to excreta
and carcasses of mule deer that had the disease," said Miller. "Our
findings show that environmental sources of infection may contribute to
CWD epidemics, and illustrate how potentially complex these epidemics may
be in natural populations."
- Added Williams, "We've had a great deal of circumstantial
evidence suggesting that indirect transmission occurs. The experimental
findings show that we need to consider several potential exposure routes
when attempting to control this disease."
- Hobbs said the research could be important in helping
to slow the spread of CWD. "Ultimately, we want to develop models
that predict the behavior of the disease," Hobbs explained. "For
example, we would like to predict how prevalence changes over time in different
areas of Colorado." Hobbs said previous disease models have been based
on animal- to animal contact as the sole source of infection and that disease
prevalence was expected to decline as the number of infected animals was
reduced. "Our findings that contaminated environments can cause transmission
means that these declines in infection rates may be much slower than would
be predicted by models that only consider animal-to-animal transmission."
Miller said that while the research shows environmental contamination is
possible in a captive setting, the impacts in the wild are still unknown.
- The research confined healthy deer in 3 sets of separate
paddocks. In the 1st set, healthy deer were exposed to another deer already
infected with CWD; in the 2nd set, deer were exposed to carcasses of deer
that had died of CWD; in the 3rd set, deer were confined in paddocks where
infected deer had previously been kept. A few of the healthy deer contracted
CWD under all 3 exposure scenarios over the course of one year.
- Chronic wasting disease is a fatal neurological ailment
of elk, white-tailed deer and mule deer. Most researchers believe the disease
is caused by an aberrant prion protein that misfolds in the brain, destroying
brain tissues as it progresses. Clinical signs include lethargy, excessive
salivation, loss of wariness of predators and slowly deteriorating body
condition. The disease is always fatal and there is no known cure or treatment
to prevent CWD.
- Federal and state health officials have found no connection
between CWD and human health. As a precaution, officials recommend that
the meat of animals infected with CWD should not be eaten.
- "Although live deer and elk still seem the most
likely way for CWD to spread geographically, our data show that environmental
sources could contribute to maintaining and prolonging local epidemics,
even when all infected animals are eliminated," Miller said. He said
the appropriateness of various culling strategies may depend on how quickly
the CWD agent is added to or lost from the environment.
- media contact:
- Cheryl Dybas firstname.lastname@example.org 703/292-7734
- -- ProMED-mail <email@example.com>
- [Then one has to wonder whether this is an infectious
disease, and is the prion an infectious agent? This is perhaps a rhetorical
question and may not yet have a justifiable answer. - Mod.TG]
- Patricia A. Doyle, PhD Please visit my "Emerging
Diseases" message board at: http://www.clickitnews.com/ubbthreads/postlist.php?Cat=&Board=emergingdiseases
Zhan le Devlesa tai sastimasa Go with God and in Good Health